As known, stacks of this type are conveniently used to generate electric power using the electrochemical reaction between hydrogen and oxygen, producing only water and are, therefore, considered a source of clean energy from the environmental point of view. The number of cells stacked in series to form the stack determines the total voltage thereof.
A stack of this type is, typically, the main component of a power generator. For correct operation, within a power generator, the stack is typically fluidically connected to a feeding and discharge circuit of gaseous currents of reactants and products, and to a cooling system (comprising, in turn, a pump, pipes, dissipaters, etc.) through which a fluid passes, e.g. water, and designed to remove excess heat from the stack developed by the above mentioned electrochemical reaction. In addition, the stack is generally operatively linked to a control system adapted to monitor a number of critical physical quantities (temperature, flow, pressure, voltage of single cell, total voltage, etc.).
To take into account above all the particular employment conditions which are utilized at an increasing extent (for example, to account for the use of a fuel cell generator as a source of electric back-up power) there is, in the field, the need to reduce the overall size of the group formed by the stack and by the auxiliary components to which it is connected within the generator, so as to reduce, therefore, the overall size and weight of an electric power generator that uses the stack itself.
Increasingly, therefore, in the art there is a need to provide a stack of fuel cells in which an increased compactness is accompanied by an improved efficiency, for example in terms of thermal integration and energy exchanges, ensuring generally high standards of performance and reliability. Moreover, it is highly desirable to provide a fuel cell stack which is compact and efficiently controllable and which has reduced response times, in order to ensure compliance with the requirements of electric power users.